Automatic sheet feeding mechanism for relief stamping machines



Feb. 14, 1939. R. D. GIFFORD ,1

AUTOMATIC SHEET FEEDING MECHANISM FOR RELIEF STAMPING MACHINES 'Filedmarch so. 1938 4 Sheets-Sheet 1 jwvenfor RANDOLPH D. GIFFORD y Feb. 14,1939. R GIFFORD 2,147,529

AUTOMATIC SHEET FEEDING MECHANISM FOR RELIEF STAMPING MACHINES FiledMarch 30, 1938 4 Sheets-Sheet 2 &

,l'flmenfor mmnotm n GIPFmD Feb. 14, 1939. WP-0RD 2,147,529

AUTOMATIC SHEET FEEDING MECHANISM FOH RELIEF STAMPING MACHINES FiledMarch so, 1958 4 Sheets-Sheet s Ina- 72302 RANDOLPH Dc GIFF OR!) BY 044WA'ITGRNEYB 1 Feb. 14, 1939. R. D. GIFFORD: 2,147,529

AUTOMATIC SHEET FEEDING MECHANISM FOR RELIEF STAMPING MACHINES FiledMarch 30, 1938 4 Sheets-Sheet 4 [14 van Z0 2 RANDOLPH D. GIFFORD ATTmums Patented Feb. 14, 1939 UNITED STATES PATENT OFFICE AUTOMATIC SHEETFEEDING MECHANISM FOR RELIEF STAMPING. MACHINES Application March 30,1938, Serial No. 198,994 In Great Britain April 1, 1937 7 Claims.

This invention has reference to the machines technically known in theprinting industry as relief stamping machines and is concerned moreparticularly with machines of the well known type wherein an engravedplate or die is mounted in a carriage which slide in guides on the frameof the machine for bringing the plate or die, face downwards, to theposition in which the printing operation is effected by the co-operationwith the die when in this position of a ram or plunger-which is raisedto bring the sheet to be printed, which sheet is fed between the die andplunger, into contact with the die for the impressing operation, theplate or die in its motion to and from the printing position beingsubjected to the necessary inking and scraping or wiping operations in amanner well understood. For examples of such machines reference may bemade to British patent specifications Nos. 174,436 and 310,073.

Heretofore the feeding of the sheets to such relief stamping machineshas been effected by hand.

The present invention has for its object the provision of automaticsheet feeding mechanism for relief stamping machines of the typeaforesaid, the said mechanism being simple in construction and efficientin operation and being attended with the further advantage that it canbe readily applied to existing relief stamping machines withoutnecessitating any material alterations thereto. 1

The invention consists of an automatic sheet feeding mechanism forrelief stamping machines of the type aforesaid, said feed mechanismbeing characterised by the association of a positively actuateddisplaceable sheet gripping device which receives a sheet deliveredsingly from a pile by sucker feed or equivalent mechanism to an initialfeeding position and progresses it from this position to the stamping orimpressing position, and a positively actuated simultaneouslydisplaceable sheet gripping device which subsequently transfers theimpressed sheet from the stamping position to a delivery point.

The invention further resides in the hereinafter described details ofconstruction and assembly or combination of parts constituting anautomatic sheet feed mechanism for relief stamping machines of the typeaforesaid and in the provision in conjunction therewith of means, alsohereinafter described, serving, in the event of failure in the feedingof a sheet between the impression die and ram, automatically to put intooperation the means ordinarily provided, and

usually operable by hand, for checking the motion of the member which inthe normal working of the machine effects the lifting of the impressionram so as to prevent it from coming into its operative contact with thesaid ram, thus 5 avoiding the soiling of the ram which would, in theabsence of a sheet, result from its direct contactwith the inked face ofthe die.

The invention will be further and more particularly described withreference to the accompanying drawings which illustrate its applicationto a relief stamping printingmachine constructed in accordance with thegeneral practice for hand feeding so much only of the ordinary machinebeing shown as is necessary to the full appreciation of the mechanismconstituting the present invention and its operation in the running ofthe machine.

Figure 1 is a front elevation the said figure showing at the left handside thereof sucker feed mechanism of known type whereby the sheets froma stack are fed singly to the initial position in which they arecorrectly placed to come under the operation of the mechanismconstituting the present invention. 1

Figure 2 is an elevation viewed from the right hand side of the machine.

Figure 3 is a similar elevation viewed from the left hand side, thesucker feed mechanism being omitted from both these figures in order toavoid confusion.

Figure 4 shows a plan of a portion of the mechanism detached, and

Figure 5 is a fragmentary portion of the same part in end elevation.

The same letters and numerals of reference indicate the same parts inthe several figures.

The main framework of the ordinary machine is denoted generally by thereference A, and B denotes generally the sucker feed mechanism wherebythe sheets from a stack C are delivered singly on to the feed table Dand it will be appreciated that this sucker feed mechanism which differsin no essential respect from such mechanisms as ordinarily employed inconnection with various types of printing machines forms no part of thepresent invention, and simply functions as means for feeding the sheetssingly to the point at which they come under the operation of themechanism constituting the invention.

The automatic feed mechanism constituting the present invention andwhereby the sheets which are fed singly to the table D by the suckermechanism B, are progressed through the printing machine from the saidtable D to a delivery 55 point such as a conveyor, indicated at E inFigure 1, at the opposite side of the machine, em-- bodies a member 'Ihereinafter referred to as the slide mounted so as to be capable of areciprocable horizontal motion in a guiding carrier 8 constituted by apreferably dovetail grooved bar adapted to be secured, as for example bybrackets I3 and bolts 8 in suitable location on the front face of theframing A of the ordinary machine.

The reciprocation of the said slide 1, for the purpose hereinafter moreparticularly described, is effected in the desired synchrony with theusual motions of the carriage of the printing plate or die 9 and theco-acting ram ID by coupling the said slide I with the horizontal shaftII which shaft supports the lever members to which the carriage of thedie 9 is connected and by the operation of which the die is brought toand removed from the printing position in a manner well understood.

This shaft I I partakes, in the ordinary operations of the machine, of arocking or partial turning motion in its bearings on the framing A andthis rocking motion is utilized for effecting the reciprocatory motionsof the slide 1, convenient means for this purpose comprising an arm I2mounted on the said shaft I I and acting under spring control on a rodI3 disposed transversely to the axis of the shaft II, the forward end ofthe said rod being pivotally connected to one arm of a bell-crank leverI4 mounted in a bearing bracket I5 provided in suitable location on theframing A, the second arm of the said bell-crank lever having pivotalconnection with a link I6 connected to the shorter arm of a bentlever-like member I! turning on the fulcrum II projecting from the frontface of the framing of the machine, the said lever I I being pivotallycoupled at its other end by a rod I8 to a bracket I on the slide I.

The arm I2 on the shaft II may be keyed directly to the shaft, oralternatively it may be made free to turn thereon in which case it isprovided, as shown, with an extension I2 which lies against a similarpart I2 on a collar keyed to the shaft II and to which part I2 it can belocked bya screw pin I2, this alternative arrangement permitting, by thewithdrawal of the screw pin I2 the machine to be run without operatingthe slide I and parts in connection therewith, that is to say, to run asan ordinary machine, which may be desirable for making ready purposes,or in the event of a breakdown in the automatic feed mechanism.

The said slide 1, which is shown in Figure l of the drawings in theextreme right hand position to which it can be brought in the carrier 8by its operating lever I1, is furnished on its forwardly presented sidewith brackets 1 1 to which are respectively fixed the verticallydisposed bars I9 and 20 which serve for the mounting on and connectionwith the slide I of the gripping devices I9 and 2!) which act inassociation with each other, as hereinafter described, .to effect thepassing of the sheets operated on from the table D to the delivery pointE, the said grippers I9 and 20 being hereinafter referred torespectively as the feed gripper and the delivery gripper.

The gripper carrying bars I9 and 20 are so disposed on the slide I andso relatively spaced apart from each other that when the said slide 1has travelled from the position shown in Figure 1, inwardly to its otherextreme position in the carrier 8, the feed gripper I9 is brought to theposition in which it can grip the sheet which has been placed inreadiness on the feed table D by the sucker feed mechanism B, andsimultaneously the delivery gripper 20 is brought to a substantiallycentral position relative to the die 9 for the gripping of the sheetwhich has already been brought by the feed gripper I9, on the previousoutward motion of the slide I, to the printing position.

The feed and delivery grippers I9 26 are of the pincer type theirlever-like gripping arms or fingers being pivoted on the lower ends ofthe bars I9 and 20, and their opening and closing motions being effectedby the action on the heels or short arms thereof of a block 2I ofsquare, or other suitable formation, which is rocked through a link 22,the links of the respective blocks being operated by the rods I 9' and20 disposed and slidable in guides I9 and 20 on the bars I9 and 20.

These rods I9 and 20 are adapted for operation at the requisite times bya series of levers 23, 24, 25 and 26 which are actuated by cams 23 24 25and 26 on a rotating cam shaft 21 supported in bearings in pedestals 8provided on the upper side of the carrier 8, the disposition of thesecams and levers being best seen in the plan view shown in Figure 4.

The cam actuated levers 23, 24, 25 and 26 are mounted and turn on thespindle 28 which may be carried by the pedestals 8, and the said leversare of a bell-crank-like formation the ends of the arms thereof on whichthe cams on the shaft 21 act being preferably furnished with rollerswhile their other and forwardly projecting ends are or may be providedwith flattened parts or ear pieces 23*, 24 25 and 26* which lie in theplane which is traversed by the gripper rods I9 and 20 in thereciprocating motions of the slide I, and when, at the appropriatetimes, the traverse of the slide I brings the upper ends of the rods I9and 20* into operative position relative to the cam actuated levers, thelevers 23 and 25 will respectively act to depress the rod which isbrought thereunder for effecting the closing of the gripper fingers, andthe levers 24 and 25 will likewise at the appropriate time, and by theiraction respectively on the overhanging part I9 20 provided on the upperends of the said rods I9 and 20 and which ends are preferably furnishedwith screw set pins I9 211 act to lift the said rods and thereby openthe gripper fingers, and it will be appreciated that the setting of thecams on the cam shaft 25, and the levers actuated thereby, is soarranged that their operative action on the gripper controlling rods I9and 20 is synchronized with the other operations of the machine.

The cam shaft 21 may be driven from an existing driven shaft 29 of theordinary machine by the provision on the said shaft 29 of a sprocket 30geared by the drivingchain 3| to a similar sprocket on the cam shaft.

The correct positioning of the sheets delivered to the feed table D bythe sucker feed B, or equivalent mechanism, is effected by the provisionat this end of the machine of side and back lay devices.

The side lay may be constituted by a pair of lever-like members 32,fulcrumed on a transverse spindle 33 one end of which has a bearing onthe frame and its other end a bearing on the lower end of a bar 34depending from the carrier 8, the operation of the said lay, for raisingthe sheet restraining downwardly bent ends of the lever-like members 32out of the path of the sheet to be removed from the table, beingeffected at the requisite times by the action, on the rod 55 inconnection with one of the lever-like members, of a lever 36 which comesunder the operation of a cam on the cam shaft 21, the said lever 35being fulcrumed on a spindle 28 mounted in the pedestals 8 hereinbeforereferred to on the carrier 8.

The back lay 31, which is of known type, is mounted on the frame of themachine so that its acting front end is in proper location relative tothe table D and the requisite sliding movements of the said back lay maybe effected through the medium of two bell-crank levers 38 and 39fulcrumed on the main framing and interconnected by the rod 40, thelever 38 being in operative connection with the lay and the lever 39coming under the action of a cam 4| on the rotating shaft 29 from whichthe cam shaft 2'! is driven.

The sheet which is taken from the table D by the feed gripper m issupported in its passage to the impression position and thence to thedelivery point E by a bed plate 42 which may be constituted by a plateof steel suitably gapped to permit the upper end of the ram to risetherethrough, the said plate being supported along its front and rearedges by the longitudinal bars it carried by brackets 44 on the mainframe and in order to prevent the leading edge of the sheet, which sheetis indicated by the dotted line X in Figures 2 and 3, from wavingupwardly ribbons 45 preferably of strip-steel and supported from theframe by brackets such as 46 may be provided, the said ribbons 45 beingdisposed slightly above and extending along the front and rear edges ofthe bed plate 42.

A dabber finger or rod 41 may be provided to hold the positioned sheetagainst the table D until the said sheet is gripped by the feed gripperW the said dabber finger 41 being operated by the connection of itsupper end to a lever 4! fulcrumed on the aforementioned spindle 28 andactuated by a cam on the cam shaft 21, and a second and similarlyoperated dabber 48 may be provided for holding the sheet when on the bedplate 42.

The action of the mechanism thus far described is briefly as follows:-

When the shaft II has in the ordinary running of the machine turned tothe position in which the arm [2 is rocked to the position seen in thedrawings the die 9 will be in position for the impression operation andat this moment the slide 7 is at the end of its outward stroke in thecarrier 8, the feed gripper bar I9 then being at the centre of themachine and simultaneously, or practically so, the feed gripper W hasbeen opened by the action on the lever 24 of the cam 24 and the dabberfinger 4 8 depressed by operation on the lever 48 of the cam a t so thatif a sheet has been brought from the bed D to this position by theprevious operation of the machine it is released, impressed and held bythe dabber practically simultaneously.

When the feed gripper I9 is in this position the associated deliverygripper 20 has been brought by its bar 20 to the delivery point E and ifa sheet has been on the previous motion of the gripper in the inwarddirection picked up at the impression point it is now released at thedelivery point, the gripper 20 being opened at the requisite moment bythe action on the lever 26 of the cam 26*.

When the shaft II is rocked in the reverse direction to withdraw the diefrom the impression point, the inward motion of the slide 1 therebybrings the feed gripper 19 to the bed D for picking up the next sheet tobe operated on, which sheet has been deposited in readiness andcorrectly laid on the bed by the operation of the lays already describedand held by the dabber 4'! to the bed D pending removal therefrom by thegripper Ill which is closed on the sheet by the action of the cam 23 onlever 23 at the appropriate moment, and at the same time the associatedgripper 20 has been brought to the central position and closed under theaction of the cam 25 on the lever 25, on the impressed sheet waitingremoval from this position,

It will be appreciated that the cams on the shaft 21 and the partsactuated thereby are so disposed and timed to operate that the sheetsare fed automatically through the machine without strain on or damage tothe sheets.

Machines of the type to which the automatic feed mechanism abovedescribed is applied ordinarily embody means, actuated by the operator,whereby, without stopping the running of the machine, the lifting of theram in into contact with the die or impression plate 9 can be checkedwhen the operator is not feeding sheets to the machine thus avoiding thesoiling of the ram by coming into contact with the inked die or plate.The said means ordinarily comprise a trip finger 49 pivoted adjacent theupper end of an arm 50 mounted on the spindle 5| on which the arm 52,linked to and exercising control on the motion of the member 53 of thetoggle mechanism, turns, the said trip finger being under the control ofa lever 54 fulcrumed on the arm 50 and which is rocked by a rod 55, thelower end whereof has a bearing on the arm 56 of a counterpoised leverfulcrumed on the frame. The said rod 55 partakes of an upward motionwhen the arm 52 is moving forwardly to bring the toggle member 53 intothe operative position relative to the part I of the ram [0 on which itbears to raise the said ram to the impressing position, the upwardmovement of the rod 55 turning the lever 54 to such position as willpermit the finger 49 to turn out of the path of the forwardly moving arm52, and thus allow the toggle member 53 to come into full operativeeffect on the ram Hi. When however it is desired to avoid the lifting ofthe ram without stopping the machine a pawl 58 mounted on the upper endof the arm 50 above the finger 49 is so moved, by the turning down ofits operating handle 58 as to bring the pawl into a locking engagementwith a projection 49 on the finger 49 which is thus maintained in aposition in which it will engage with the shoulder 52 on the upper endof the arm 52 thus arresting the forward movement of the said arm andthrough its link connection with the toggle member 53 turning the saidmember in the direction Which will prevent it from coming into operativebearing on the ram I0.

Means whereby this check mechanism can be brought automatically intooperation in the event of the automatic sheet feeding mechanismhereinbefore described failing to feed a sheet, are comprised in thepresent invention said means being operable from the cam shaft 2'! andembodying the provision of a pair of needles 59 such as are customarilyemployed in connection with check mechanisms in paper sheet feeding mchines, the said needles being carried by arms 60 on a spindle 6|disposed transversely across the bed D and supported in bearings inbrackets fixed to the frame of the machine, the free ends of the saidneedles resting, when a sheet of paper is fed on to the bed, on theupper surface of the said sheet but when no sheet is delivered, the saidends rest on the bed and can engage with depressions 62 formed therein.

Ihe spindle 6| has an arm 62 connected by the rod 63 to a lever 64 onthe spindle 28 which lever is rocked by the action of a cam 64 on thecam shaft 21, thereby effecting a rocking of the needle spindle 6| andgiving to the needles a slight to-and-fro motion over the surface of thesheet of paper when a sheet is on the bed D. When however no sheet ispresent on the bed the needle ends drop into engagement with theaforesaid depressions 62 on the bed and arrest the rocking of thespindle 6| and, through the rod 63, of the lever 64. Connected to theend of the said lever 64 is a wire cable 65 which passes therefrom overa series of guide pulleys 66 to a connection with the arm 61 dependingfrom the spindle 68 which extends across the lower front edge of theframing and has bearings in the opposite sides thereof. Mounted on thespindle 68 is a weighted arm fil which co-operates with the arm 61 intending to maintain the cable 65 taut.

So long as sheets are fed on to the bed D the needles 59 move freely andthe end of the lever 64 is moved downward on each revolution of the camshaft 21 thus slackening the cable and pe mitting the turning of thespindle 68 under the action of the weighted arm 61 This turning of thespindle 68 lifts the rod 55, through the action thereon of the bracket56 which is carried by the spindle 68, with the result that the checkfinger 49 turns to a non-acting position relative to the arm 52, butwhen no sheet is delivered to the bed D the free forward motion of theneedles 59 is arrested by the engagement of their ends with thedepressions 62 in the bed the turning of the needle spindle 6| isprevented, and consequently the rod 63 which connects the spindle 6|with the lever 64, holds the said lever against a downward turningmotion with the result that the cable 65 is preserved taut, and preventsthe turning of the spindle 68 which is necessary for the lifting of therod 55 of the check mechanism, and thus the lever 54 which acts on thecheck finger and is operated by the rod 55, maintains the check finger49 turned into the path of the shouldered upper end of the arm 52,thereby preventing the toggle member 53 coming into operation on theram.

It will be appreciated that when the machine is running on automaticfeed the handle 58 remains turned to the position in which the pawl 56is out of contact with the projections 49 on the check finger 49.

What I claim is:--

1. An automatic sheet feed mechanism for use in connection with reliefstamping machines of the type hereinbefore referred to, said sheet feedmechanism embodying in combination, a slide having a plurality of sheetgripping devices mounted thereon, a carrier capable of being fixed tothe frame of the stamping machine and supporting said slide forhorizontal reciprocatory motion, lever and link means adapted to beconnected to a driven shaft of the stamping machine for operating saidslide, a cam shaft extending longitudinally over the slide carrier andhaving means for connecting it to a driven shaft of the machine to bedriven continuously therefrom, a plurality of cams on the said camshaft, lever members fulcrumed adjacent the cam shaft and rockable bysaid cams, and means having connections with the reciprocable grippingdevices and operable by said lever members to effect at the requisitetimes the opening or closing of the said devices.

2. Automatic sheet feed mechanism in accordance with claim 1, includinga side lay device embodying a spindle having pivotal members fulcrumedthereon, one end of said spindle having a bearing in a bar dependingfrom the carrier of the reciprocable slide, and a rod having aconnection with a lever arm fulcrumed adjacent the cam shaft andactuated by a cam on the said cam shaft for operating said pivotalmembers.

3. Automatic sheet feeding mechanism as claimed in claim 1, including aback lay mounted on the side frame of the machine, and operating meanstherefor embodying two interconnected bell-crank levers fulcrumed on theside frame of the machine, one of the said levers having operativeconnection with the back lay and the other being operable by a cam on adriven shaft of the machine.

4. Automatic sheet feed mechanism in accordance with claim 1, includingdabber fingers, and lever members fulcrumed adjacent the cam shaft overthe carrier, and operable by cams on the said cam shaft to control saidfingers.

5. Automatic sheet feed mechanism in accordance with claim 1, whereinthe carrier for the reciprocable slide is provided on its upper sidewith pedestals having bearings for the cam shaft and carrying parallelrods constituting the fulcrums for the lever members provided thereonand operable by the cams on the cam shaft.

6. Automatic sheet feed mechanism in accordance with claim 1, includinga gapped bed plate supported on longitudinal bar members carried bybrackets provided on the side framing of the machine, and a plurality oflongitudinally extending metallic ribbons suitably supported on the sideframing of the machine and disposed over said bed plate.

7. Automatic sheet feed mechanism claimed in claim 1, for use inconjunction with relief stamping machines of the type having a toggleram, toggle check mechanism and a trip finger, including means foreffecting automatically the bringing into operation of the checkmechanism without stopping the running of the machine, said meansembodying a cable having one end thereof connected to a rockable member,a rod on which said rockable member is adapted to act and which controlsthe operation of the trip finger of the toggle check mechanism, a leverto which the other end of said cable is connected and-operable by a camon the cam shaft of the automatic sheet feed mechanism, and a rockablespindle coupled with said lever and located over the feed bed andcarrying needles the free ends whereof move over the surface of thesheet when a sheet is on the bed, but which needle ends in the event offailure in the sheet feed engage with depressions in the bed therebyarresting the rocking of said rockable spindle and preventing theturning of the lever coupled therewith and which controls the motions ofthe cable which interconnects the said lever with the mechanismcontrolling the toggle check mechanism.

RANDOLPH DOUGLAS GIFFORD.

